I create a new project in java springboot. When I try to run the code it gives the following error.

D:\Project\New folder\demo\src\main\java\com\example\demo\controller\EmployeeController.java:15:35 java: variable employeeService not initialized in the default constructor

My entity class

package com.example.demo.entity;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import lombok.Data;
@Entity
@Data
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    private String name;
    private String email;
    private String phone;
    private String department;
}

My Repository class like this

package com.example.demo.repository;
import com.example.demo.entity.Employee;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface EmployeeRepository extends JpaRepository<Employee, Long> {
}

My service class

import com.example.demo.entity.Employee;
import com.example.demo.repository.EmployeeRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
@Service
@RequiredArgsConstructor
public class EmployeeService {
    private final EmployeeRepository employeeRepository;

    public Employee postEmployee(Employee employee) {
        return employeeRepository.save(employee);
    }

}

My Controller class

package com.example.demo.controller;
import com.example.demo.service.EmployeeService;
import lombok.RequiredArgsConstructor;
import org.springframework.web.bind.annotation.*;
import com.example.demo.entity.Employee;

@RestController
@RequestMapping("/api")
@RequiredArgsConstructor
public class EmployeeController {
    private final EmployeeService employeeService;
    @PostMapping("/employee")
    public Employee postEmployee(@RequestBody Employee employee) {
        System.out.println(employee);
        return employeeService.postEmployee(employee);
    }
}

pom.xml file

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns=".0.0" xmlns:xsi=";
         xsi:schemaLocation=".0.0 .0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.4.0</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>employeeserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springserver</name>
    <description>Demo project for Spring Boot</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.36</version> <!-- You can use the latest stable version -->
            <scope>provided</scope> <!-- This makes Lombok available at compile-time only -->
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

I searched in several AI tools and searched in the Web. I didn't find any solution. AI tools mentions this code is correct. I want a solution for this error.

I create a new project in java springboot. When I try to run the code it gives the following error.

D:\Project\New folder\demo\src\main\java\com\example\demo\controller\EmployeeController.java:15:35 java: variable employeeService not initialized in the default constructor

My entity class

package com.example.demo.entity;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import lombok.Data;
@Entity
@Data
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    private String name;
    private String email;
    private String phone;
    private String department;
}

My Repository class like this

package com.example.demo.repository;
import com.example.demo.entity.Employee;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface EmployeeRepository extends JpaRepository<Employee, Long> {
}

My service class

import com.example.demo.entity.Employee;
import com.example.demo.repository.EmployeeRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
@Service
@RequiredArgsConstructor
public class EmployeeService {
    private final EmployeeRepository employeeRepository;

    public Employee postEmployee(Employee employee) {
        return employeeRepository.save(employee);
    }

}

My Controller class

package com.example.demo.controller;
import com.example.demo.service.EmployeeService;
import lombok.RequiredArgsConstructor;
import org.springframework.web.bind.annotation.*;
import com.example.demo.entity.Employee;

@RestController
@RequestMapping("/api")
@RequiredArgsConstructor
public class EmployeeController {
    private final EmployeeService employeeService;
    @PostMapping("/employee")
    public Employee postEmployee(@RequestBody Employee employee) {
        System.out.println(employee);
        return employeeService.postEmployee(employee);
    }
}

pom.xml file

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.4.0</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>employeeserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springserver</name>
    <description>Demo project for Spring Boot</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.36</version> <!-- You can use the latest stable version -->
            <scope>provided</scope> <!-- This makes Lombok available at compile-time only -->
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

I searched in several AI tools and searched in the Web. I didn't find any solution. AI tools mentions this code is correct. I want a solution for this error.

• java
• spring-boot
• constructor
• runtime-error

• This question is similar to: Build Failure: @Data Annotation won't regonize by Maven. If you believe it’s different, please edit the question, make it clear how it’s different and/or how the answers on that question are not helpful for your problem. – Sören Commented 2 days ago
• 3 Are you sure that's the code of your service class? Looks to me like it's the code of your main application class – JustAnotherDeveloper Commented 2 days ago
• Where is the code of the service class? additionally add you pom.xml in your question. – Syed Commented 2 days ago
• Try Autowire instead of RequiredArgsConstructor. Remove RequiredArgsConstructor and on top of EmployeeService add Autowire. – Govil Kumar Commented yesterday
• @JustAnotherDeveloper , That's my mistake. I corrected it. Thank you. – Madavi Fernando Commented 15 hours ago

1 Answer 1

I have added the same code to my project, and the application has started successfully, as you can see in the picture below. You need to reload the Maven project properly, as shown in the screenshot below.

Below is my pom.xml